Evaluation of Hemolysis

Last updated: April 6, 2026, 6:50 PM Pacific Time (PDT)

Interactive bedside framework for suspected hemolysis. Start by confirming a real hemolysis pattern, then sort immune hemolysis, TMA / mechanical hemolysis, enzyme or membrane disorders, and secondary hemolytic syndromes.

Interactive diagnostic assistant

Activate the assistant to rank hemolysis mechanisms and diagnoses once the entered data support more than 50% confidence.

Hemolysis pattern LDH (U/L, often high in hemolysis)
Haptoglobin (mg/dL, often low in hemolysis)
Indirect bilirubin (mg/dL, often high if hemolysis is significant)
Reticulocyte response

History and bedside clues Jaundice, dark urine, scleral icterus, or pigment symptoms Recent transfusion or transfusion-reaction concern Autoimmune disease, lymphoproliferative disorder, or warm-AIHA context Cold-triggered symptoms or acrocyanosis Schistocyte, thrombocytopenia, renal injury, or TMA concern Mechanical valve or circulatory-device shear concern Drug-triggered hemolysis or oxidant exposure concern Family history or chronic inherited hemolysis context

Other labs

Core labs

Peripheral smear
Hemoglobin (g/dL, ref about 12-17 depending on sex)
Platelets (k/uL, ref about 150-450)

Optional labs

Direct antiglobulin test / DAT
Creatinine (mg/dL, ref about 0.6-1.3)
Coagulation / DIC context
G6PD / membrane-disorder context
Urinalysis / hemoglobinuria context

Core hemolysis labs are LDH, haptoglobin, indirect bilirubin, reticulocyte response, smear, hemoglobin, and platelets. DAT is supportive but optional. Free-text entries are interpreted automatically when they look high, low, positive, negative, schistocytic, spherocytic, or otherwise clearly abnormal.

Likely mechanisms

Likely diagnoses from entered data

This is a simplified teaching assistant for bedside hemolysis reasoning. Rapid anemia with TMA features, severe transfusion reaction, or profound intravascular hemolysis still needs immediate escalation.

Flowchart

Step 1

Confirm a real hemolysis pattern first

LDH up, haptoglobin down, indirect bilirubin up, and a reticulocyte response usually get you most of the way there.

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Step 2

Use DAT and smear to narrow the mechanism

DAT-positive disease, schistocytes, spherocytes, bite cells, and device history all point in different directions quickly.

Immune hemolysis

Warm

Warm autoimmune hemolytic anemia

DAT-positive disease with spherocytes and autoimmune or lymphoid context belongs here.

Cold

Cold agglutinin or complement-mediated disease

Cold-triggered symptoms and complement-heavy DAT patterns are classic clues.

Microangiopathic or mechanical hemolysis

TMA

TMA, TTP, HUS, malignant hypertension, DIC

Schistocytes plus thrombocytopenia or organ injury should pull you here urgently.

Shear

Mechanical valve or device-related hemolysis

Think shear when the hardware story is obvious.

Intrinsic RBC disorders

Enzyme

G6PD deficiency or oxidant-triggered hemolysis

Bite cells, oxidant triggers, and episodic hemolysis are useful clues.

Membrane

Hereditary spherocytosis or other membrane disorders

Chronic hemolysis plus family history lives here.

Secondary or mixed hemolysis

Reaction

Transfusion reaction or acute secondary hemolysis

The timeline matters a lot when hemolysis follows transfusion or a clear trigger.

Mixed

Liver disease, infection, malignancy, or secondary hemolytic syndromes

Not every hemolysis picture is purely immune or purely intrinsic.

Teaching pearl: DAT and smear are often the highest-yield next studies after confirming that true hemolysis is happening.